Mobile hydraulic crane



Nov. 3, 1959 Filed Nov. 27, 1956,

J. L. GROVE 7 2,911,111

MOBILE HYDRAULIC CRANE 6 Sheets-Sheet 1 INVENTOR BY g l v ATTOREY NOV. 3, 1959 J, GROVE 2,911,111

MOBILE HYDRAULIC CRANE Filed Nov. 27, 1956 6 Sheets-Sheet 2 J1 INVENTOR Nov. 3, 1959 J. L. GROVE 2,911,111

MOBILE HYDRAULIC CRANE 6 Sheets-Sheet 3 Filed Nov. 27, 1956 INVENT OR Jam/ 1.. em/5,

BY Q J ATIONEY Nov. 3, 1959 J. L. GROVE MOBILE HYDRAULIC CRANE 6 Sheets-Sheet 4 Filed Nov. 27, 1956 I INVENTOR JOA A L. 6R0 v5,

A'ITOR Y Nov. 3, 1959 J. L. GROVE MOBILE HYDRAULIC CRANE 6 Sheets-Sheet 5 Filed Nov. 27, 1956 INVENTOR JO/M/ z. 680 1 5,

8 all A'T'I'OR EY Nov. 3, 1959 ,J. L. GROVE MOBILE HYDRAULIC CRANE 6 Sheets-Sheet 6 Filed NOV. 27, 1956 llll in:

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ATToK/VEY United States Patent My invention relates broadly to cranes and more particularly to a. compact construction of heavy duty mobile crane.

One of the objects of my invention is to provide a construction of crane in which loading and unloading operations may be accomplished by telescopic operation of a sectionalized boom without the necessityof winches for winding or unwinding cable on a cable drum.

Another object of my invention is. to provide a construction of mobile crane in which a telescopic sectionalized boom is controlled by a complement of hydraulic cylinders arranged interiorly of the sectionalized boom and control1able from a crane operators position for extending or retrieving a hoist line.

Still another object of my invention is to provide a construction of mobile crane which is substantially balanced and maintained in equilibrium under varying conditions where the boom may be slewed or oriented, topped or telescoped either under load or no load.

A further object of my invention is to provide a construction of mobile crane having a hydraulically controlled telescopically arranged boom so balanced that a load may be raised from base level of the mobile crane without the necessity of topping the boom and while maintaining a constant length or" cable while the boom is being topped or slewed, or sections of the boom telescoped under hydraulic control.

A still further object of my invention is to provide an arrangement of hydraulic control means for slewing or orienting the turntable of a mobile crane to swing the boom into position where such means are constituted by hydraulic cylinders capable of selective operation for control of the directional flow of the fluid in the hydraulic cylinders for directionally controlling the movement of the boom.

Other and further objects of my invention reside in the compact assembly of hydraulic operated means for a mobile crane whereby the elevation, projection and orientation of the boom may all be hydraulically controlled from an operators station on the mobile crane as set forth more fully in the specification hereinafter following by reference to the accompanying drawings, in which:

Fig. l is a perspective view of the mobile crane of my invention showing the association of the controls with the crane;

Fig. 2-is a perspective view of the crane of my invention illustrating particularly the elevating and slewing hydraulically controlled cylinders;

Fig. 3 is a vertical longitudinal sectional view through the c'rane and the hydraulic control mechanism associated therewith;

Fig. 4 is a longitudinal sectional view through the telescopic sections of the boom taken on line 4-4 of Fig. 3;

Fig. 5 is a perspective view of one of the control cylinders and associated cable control means contained within the telescopic boom;

Fig. 6 isa top' planview. of the hydrauliccylindenand associated mechanism illustratedinFig. 5;

Fig. 7' is a longitudinal sectional view on-.line-.7+7 of Fig. 6;

Fig. 8' is a fragmentary, perspective view'of, one end of the coacting hydraulic cylinder within the telescopic sections of the boom; and 1 Fig. 9 is a plan view showing, the arrangement-oftth slewing cylinders in the'craneofmy invention.

My inventionis directed-to aconstruction of. mobile crane which is readily controllable from an operatorZs station on the mobile chassis fortoppi'ng, slewing, project- 'ing and retracting'theboomby. the telescoping of .sections of; the boom and elevating and maneuvering-the boom under close tolerances. Winches and "cable-drumsare v entirely omitted frornthe structureof my invention and precision control of all movements of thelboom isiobtainable from an operators control position ,on the. mobile unit. heboom is constructed in telescopic sections each of which isprovided with aninternal mounting forhydraulically controlled cylinders. and piston units lineally extendible and retractablerforgoverning. theeffective length of thecable which extended or retractediromth'e end of the boom. The hydraulic control cylinderswithin thesections of the boom 'include means for g'uidingthe cable around guide pulleys associated with the endsof the piston rods operative Within the hydraulic, cylinders. Thus the cable is prevented frornentanglement byv being maintained within the guide meansrassociated with the hydraulic cylinders and without'the conventional cable drum talieup arrangement. I. have applied the principles of my inventiontocranesofS-ton,capacity-providing a IO-foothoist line actuatedsolely by hydraulic means. While I have presented my invention in certain proportioned embodiments I, realize that modifications maybe made and I desire that my invention as. set forthhe'rein be considered in the illustrative sense and-not in. the

limiting sense.

Referring to the drawings in more detailwreference character 1 designates the chassis of. the mobile units'upported by wheels 2=and driven by engine 3. A basesupport 4 is provided on the chassis 1; for. theaboomwhich consist of telescopic sections 5 and 6. The telescopic sections of the boom are generally diagonal in transverse section and slideone within another, the boom section 6 telescoping within the length of the boom section. '5;.a s represented in Fig. 3. Hydraulic cylindersfT- are-provided for raising and lowering, the boom. A. cable 8.is associated with the boom and terminates in ahoisthook 9. A pair of ram cylinders 10 and-10, are employedrfor controlling the slewing of. the boom. All of the hydraulic cylinders in the crane assembly are controlled. from an operators stationll mount don chassis, 1 which includas a set of control levers pivotally mounted incontrol box 12 and marked A, B, C, and D. The mobileunitincludes steering mechanism controlled by steering wheel 13, facilities for replacement parts which I have indicated at 14, and a drivers seat, conveniently locatedwithrespect to the operators station 11, as-shown at 15;

The chassis provides mounting meansfor. the turntable 16, the rotating movement of which is controlled by the hydraulic ram cylinders 10 and 10. Y

The telescopic sections 5 and 6 of the boom provide housings for the hydraulic cylinder unitsshown at1-7' and 18. These hydraulic units occupy positions'substantially parallel to each other but displaced on longitudinal axes so that the units may operate adjacent each other in the extension and retraction of the associated; pistonfrods shown at 61 and 22, respectively. The hydraulic unit 17 terminates at one end in a transversely disposed tubular.

m r'% hichvp a ly g gesthe r n ve m mber 27 which is fixed at opposite ends in the side walls of telescopic section 6 of the boom. The hydraulic cylinder 17 pivots about the transverse member 27 and is free to angularly shift sufficiently to accommodate the reciprocation of the piston rod 61 within cylinder 17 and within the limits of the interior of section 6 of the boom. The

end of the piston rod 61 carries a yoke 87 in which there is journaled a sheave 68 within housing 59 for guiding the cable around the sheave and through telescopic guide tubes 85 which slide within guide tubes 60 secured on diametrical'sides of hydraulic cylinder 17. The tubes 85 connect to housing 59 through brackets 91. The cable 8 extendsthrough the guide tube 60 and the telescopic guide tubes 85 around the sheave 68 journaled at 69 in the bracket 87,'enabling the effective length of the cable housing within the boom to be increased as the piston rod 61 is projected and the corresponding amount of cable lowered from the end of the boom as the piston rod 61 is retracted into the hydraulic cylinder 17.

The hydraulic cylinder 18 is pivoted within the boom section adjacent one end as represented at 19 and is pivoted within the boom section 6 at the opposite end as represented at 21. The connection of hydraulic cylinder 18 with the end of boom section 5 is accomplished by means of a transverse bar 19A over which the transverse tubular head 19 on the end of hydraulic cylinder 18 fits. The other end of the hydraulic cylinder 18 is connected to the interior of telescopic boomsection 6 through piston rod 22, the tubular head 20 and the transverse bar 21 which extends across the interior of the boom section 6 on an axis which is normalto the direction of the axis of the bar 19A. Thus telescopic section 6 may be extended and retracted under control of cylinder 18 with suflicient lost motion between pivotal connections for one end of the cylinder and the pivotal connection for the end .of the piston rod 22 to assure adequate tolerances for the reciprocatory movement of the piston rod 22 with respect to the'cylinder 18. Suitable reinforcement for the cylinder 18 is obtained by the interconnecting rods 90 which extend between the headers at-opposite ends of the cylinder. V

The telescopic section 5 is provided with a bracket 67 adjacent the extreme end thereof in which a transverse roller 23 is journaled for supporting the interior telescopic section 6 in movement out of and into the hydraulic section 5. Theextreme end of the interior telescopic section 6 contains a transverse bar 28 which constitutes a journal for the sheave 24 over which the cable 8 is guided. A hood 25 is arranged on the end of the boom section 6 immediately over the cable 28 which passes around the sheave 24. The cable 8 is represented schematically as passing through'the telescopic boom sections 6 and 5 to the cable control mechanism. The end of the interior telescopic section 6 within the telescopic section 5 has a bracket .30 thereon in which rollers 58 are mounted which make contact with the undersurface of the top of the telescopic section 5, facilitating extension and retraction of the interior telescopic section 6 with respect to the exterior stationary section 5. The boom is supported by a cradle 32 which is pivoted in transverse bar 31 carried in the ends of the projectable piston rods controlled by hydraulic cylinders 7. The hydraulic cylinders 7 are pivotally mounted at their lower ends at 41 in brackets 42 mounted on the turntable 16. The

cylinders 7 coact with the telescopic cylinders 39, 66 in stabilizing the boom during the elevation and lowering thereof. The telescopic cylinders 39, 66 connect at their lower endsto brackets 40 supported from the turntable 16. The stationary section 5 is provided on its lower surface with a depending bracket 35 in which the longitudinally extending bar, 33 is pivotally mounted. The bar:33 provides a mounting means for a bracket in which guide pulley 36 is journaled. A coil spring 34 tends to continuously urge the end of the bar 33 and the guide pulley bracket supported thereby against the underside of the boom section 5 in all of the positions of telescoping thereof as the boom is raised or lowered. The boom section 5 terminates in the reinforced end structure 64 which carries the depending bracket 38 for journaling the guide pulleys 37. The guide pulleys 36 and 37 serve as guides for the flexible tube shown at B for conveying the hydraulic fluid to one of the hydraulic cylinders. Hydraulic fluid is conveyed to the other hydraulic cylinder through flexible pipe C.

The turntable mounting 16 is providedwith reinforcement means 43 supported from a base 44. There is a central passage 45 in the base 44 and the associated turntable 43 for the passage of the pipes A, B and C which control the flow of hydraulic fluid through controls A, B and C, respectively, at the operators station 11 to the elevating and lowering cylinders 7 and the hydraulic extension and retraction cylinders 18 and cable cylinder 17.

In order to provide for the slewing of the turntable 16, I arrange the ram cylinders 16 and 10' so that these cylinders control pistons which operate pistons and piston rods 47 and 47' operative through header 46 against pin 54. The cylinders 10 and 10' are pivoted at52 and 52 on pins 51 and 51 in extensions 63 and 63 of the base support 44. The turntable 16 carries a frame support 48 which braces the frame supports 55 and 57 forming the mounting means for the boom. The boom is mounted on trunnions 94 in the frame supports 57 in such manner that the boom may be raised and lowered under control of hydraulic cylinder 7 and oriented to position by angularly moving turntable 16 under control of ram cylinders 10 and 10'. These ram cylinders are selectively controlled by fluid supplied through pipe line D' controlled from controller D at the control station 12 and the control fluid by-passed between the cylinders 10 and 10' through pipe D. The turntable 16 is supported on members 62, 49 and 50 in the position whereby the turntable may be oriented by controlling cylinders 10 and 10.

The telescopic cylinder guards 39, 66 shown in Fig. 1

pivotally connect at their lower ends with the turntable 16 and at their upper ends with crank arms represented at 65 which connect with the trunnions 92 for protection of lift cylinders 7 and 7 and coacting pistons facilitating the 72 in recess 74 of header 75 and sealing means 73 in header 75 for insuring the tight seal of the end of the hydraulic cylinder. Intake and discharge connections are made to the opposite ends of the cylinder 17 as represented at 86 and 93. The piston rod 61 carries the piston secured in position between ferrule 77 and the clamping nut 81 engaging the screw threaded end of the piston rod. The piston assembly includes plates. 78 and 84 clamping the cup leathers 79 clamped in position by the nut 81. The opposite end of the cylinder is closed by the header represented at 82. The cylinder heads are secured in position by the longitudinally extending rods which pass through the headers and are clamped in position by fastening nuts 89, as shown. The crane of my invention is very readily controlled from the drivers seat 15 by operation of lever A for controlling the extension and retraction of the cable; operation of lever B for controlling the elevation and lowering of the boom; operation of lever C for controlling the projection and retraction of the boom, and operation of lever D for controlling the slewing of the boom. All of these operations are effective without the use of winches or winding have described certain preferred embodiments thereof I desire that it be understood that no limitations upon my invention are intended other than may be imposed by the scope of the appended claims.

What I claim as new and desire to secure by Letters Pattent of the United States, is as follows:

1. A crane boom comprising a multiplicity of telescopic sections slidable lineally with respect to each other, a hydraulic ram connected to at least two of said sections, a second hydraulic ram individual to the inner section of the boom, a piston in each of said rams, a piston rod individual to each of said pistons and slidable into and out of the associated ram, a sheave carried by one of said piston rods, a hoist cable secured to one of said sections and movable in a path around said sheave and through the extremity of said boom, means for conveying hydraulic pressure to said rams through said boom for selectively effecting an extension or retraction of said telescopic sections and selectively controlling the extension and retraction of said hoist cable, and in which one of said sections is pivotally mounted with respect to a chassis and wherein the means for conveying hydraulic pressure to said rams thereof consists of flexible hose and spaced pulleys located intermediate said chassis and the pivotal mounting of said sections with respect to said chassis for supplying hydraulic pressure to the said rams.

2. A crane boom comprising a multiplicity of telescopic sections slidable lineally with respect to each other, a hydraulic ram connected to at least two of said sections, a second hydraulic ram individual to the inner section of the boom, a piston in each of said rams, a piston rod individual to each of said pistons and slidable into and out of the associated ram, a sheave carried by one of said piston rods, a hoist cable secured in one of said sections and movable in a path around said sheave and through the extremity of said boom, means for conveying hydraulic pressure to said rams through said boom for selectively efiecting an extension or retraction of said telescopic sections and selectively controlling the extension and retraction of said hoist cable, and in which one of said rams is provided with a guide tube on diametrically opposite sides thereof and wherein said hoist cable extends through said guide tubes and around the sheaves through said boom for effecting an extension or retraction 6 carried by said piston rod individual to said one of said rams.

3. A crane boom comprising a first boom section pivotally supported in a cradle, a second boom section telescopically arranged to slide interiorly of the aforesaid boom section, a pair of hydraulic cylinders, piston and piston rod assemblies, one of said assemblies being connected between one end of the interior of said first boom section and a position'adjacent the opposite end of said telescopically arranged second boom section whereby extension and retraction of the last-mentioned assembly operates to project or retract said telescopically arranged second boom section with respect to said first boom section, and the other of said assemblies having one end thereof connected with said telescopically arranged first boom section in a position adjacent the extremity thereof, said last-mentioned assembly operating within said lastmentioned second boom section for the projection and retraction of the piston and piston rod therein, a sheave carried by said last-mentioned piston rod and a hoist cable extending around said sheave and through the extremity of said second boom section whereby the extension and retraction of said hoist cable is controlled by the extension and retraction of the position of said sheave with respect to said last-mentioned assembly, and in which said lastmentioned assembly includes a pair of longitudinally extending guide tubes attached to diametrically opposite sides of the associated hydraulic cylinder and wherein said hoist cable extends through said guide tubes in the course of the path of travel thereof around the said sheave ind through the extremity of the second section of the References Cited in the file of this patent UNITED STATES PATENTS France Apr. 22, 1953 

